The lack of artificial coloring caught the attention of Mark Thomann, a managing director at Spiral Sun. "They created an all-natural option. We like stories like that and we like products that can add incremental value to big categories."

The fact that Coco5 doesn't have added coloring has helped it gain traction among the youth-sport set, Thomann added, noting it's become a hit at local places including Midtown Athletic Club and Lakeshore Sports and Fitness, where his daughter plays competitive tennis.

Consumers also like it because it doesn't taste overwhelmingly like coconut, Thomann says. "The taste profile is really awesome," he says. "Coconut water is really polarizing, but this is something that a lot of people will actually drink."

The taste is was what lured Loop Capital's Reynolds, according to Coco5 co-founder Scott Sandler, a serial entrepreneur who teamed up with Gapski to bring the new drink to market.

"Jim drank it at East Bank Club and then saw me at Hawks' games and kept telling me he wanted to invest," Sandler says. "I thought he was joking. The third time he said it, he said, 'I'm serious. Let's set up a meeting.'"

Coco5's connection to professional and collegiate sports—it's in the locker rooms of more than 80 teams, according to Sandler—has been a big boon, as well. "When you look at the athlete connection from a marketing perspective, you can't put a dollar value on that," Thomann says. "It's a really great foundation on which to build a brand."

The investment is being used to increase production capability and to make several key hires, including Brad Downes, a Groupon veteran, as CFO and Leslie Butler, a former head of innovation at PepsiCo.

Coco5 posted $1 million in revenue last year and is predicting $3.6 million this year, Sandler says. Once the brand gets its footing in Canada later this year, "our next big focus will be (increasing sales on) Amazon" and continuing to expand the drink's presence outside Chicago.

"Over the next 18 months, you'll see a small Chicago company grow into a national brand," Thomann says. "We believe Coco5 can be a $100-plus million brand."